drm/i915/mtl: Add vswing programming for C10 phys

C10 phys uses direct mapping internally for voltage and pre-emphasis levels.
Program the levels directly to the fields in the VDR Registers.

Bspec: 65449

v2: From table "C10: Tx EQ settings for DP 1.4x" it shows level 1
    and preemphasis 1 instead of two times of level 1 preemphasis 0.
    Fix this in the driver code as well.
v3: VSwing update (Clint)
v4: Add vboost termination ctl programming(Imre)
    Fix tx llogic and other nits
    Restrict C10 vdr ctl register access for C10 phy(RK)
v5: Program vboots, termination ctl for both lanes(Imre)

Cc: Imre Deak <imre.deak@intel.com>
Cc: Uma Shankar <uma.shankar@intel.com>
Signed-off-by: Clint Taylor <Clinton.A.Taylor@intel.com>
Signed-off-by: Radhakrishna Sripada <radhakrishna.sripada@intel.com>
Signed-off-by: Mika Kahola <mika.kahola@intel.com>
Reviewed-by: Imre Deak <imre.deak@intel.com&gt;(v3)>
Link: https://patchwork.freedesktop.org/patch/msgid/20230413212443.1504245-5-radhakrishna.sripada@intel.com